Our aim is to develop an inexpensive and portable nanotechnology-based immunosensor and instrument platform for rapid detection of presence or exposure to bioterror agents in air, water, contaminated surfaces, forensic samples, food and body fluids through identification of protein toxins and microorganisms. The proposed approach employs single or multiple conically shaped gold nanotubes embedded within a mechanical and chemically robust polymeric membrane. The sensing measurement entails passing an ionic electrolyte current through the nanotube. Analyte in the electrolyte (e.g., a protein or virus) binds to a biochemical molecular-recognition agent such as an antibody immobilized at the small-diameter opening (or mouth) of the conical nanotube, which blocks the ion current. The approach is technically capable of registering single molecule/particle events and as such can lead to extremely low levels of detection with high specificity. The method is highly adaptable to microfluidic platforms and can be adapted to microliter sample volumes. The Phase I program will extend feasibility studies already completed at the University of Florida to developing operational parameters and assessing instrument performance for detecting model toxins in drinking water. Such instruments are envisioned as real-time monitors in buildings, subways, etc [unreadable] [unreadable]